Add Japan 独走/下克上/政変 mechanics

Four uniquely Japanese political crisis mechanics:

1. 軍部独走 (Military Acting Alone): Hidden risk meter, random unauthorized military actions
   - Korea invasion without authorization, Sakhalin border provocation, Pacific NW clash
   - Player gets no warning, must endorse or disavow (both bad)
   - Risk rises with: military frustration, national humiliation, weak PM, economic downturn

2. 下克上 (Gekokujō): Junior officer assassinations of politicians/zaibatsu
   - Fires when military anger high + reform happening
   - Player chooses: crack down, appease, or ignore

3. 軍事政変 (Military Coup): Highest stakes event
   - Requires multiple trigger conditions simultaneously
   - Success → Showa-style military dictatorship
   - Failure → civilian reform opportunity but military weakened

4. 統帥権干犯 (Supreme Command Issue): Recurring blocker on military reform
   - Military cites Emperor's authority to block budget cuts/arms reduction
   - Only bypassed through Emperor's support or civilian control reform

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

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   V3 mechanic: Colonial policy decisions affect loyalty, development, and cost for each territory
 ```
 
+### The Dark Side: 独走・下克上・政変
+
+Japan's political system has a unique flaw: **the military can act INDEPENDENTLY of the civilian government**, and subordinates can defy/assassinate superiors. These are not bugs — they're features of 150 years of militarized modernization.
+
+**1. 軍部独走 (Gunbu Dokusō — Military Acting Alone)**
+```
+  The military's 直奏権 (direct access to Emperor) means generals
+  don't NEED cabinet approval to act. They can:
+  
+  ├ Launch border provocations without government knowledge
+  ├ Invade neighboring territory "to protect Japanese interests" 
+  ├ Create fait accompli that the government must accept or disavow
+  
+  MOST LIKELY TARGETS:
+  
+  Korea (朝鲜独走):
+    Army officers on the Korea Strait → provoke incident → invade
+    "Korean government failed to protect Japanese merchants"
+    → Government didn't authorize this → now what?
+    → Disavow: humiliation + military fury + possible coup
+    → Accept: unwanted war with Korea (+ possibly Song/Jianzhou intervention)
+    
+  Sakhalin (樺太独走):
+    Army units in southern Sakhalin → attack Jianzhou positions in north
+    "Jianzhou violated the border" (fabricated or exaggerated)
+    → Could trigger full Jianzhou-Japan war that nobody in Tokyo wanted
+    
+  Pacific NW (太平洋独走):
+    Navy/settlers in Columbia region → clash with Kalmar/English/Song outposts
+    → Expands conflict to the other side of the Pacific
+    
+  V3 MECHANIC:
+  → Hidden "独走 risk" meter — rises when:
+    ├ Military faction is strong but frustrated (wants war, government says no)
+    ├ National humiliation event occurs (treaty port issue, diplomatic loss)
+    ├ Economic downturn (unemployed soldiers, nationalist anger)
+    ├ Weak Prime Minister / political instability
+  → When meter fills → RANDOM 独走 event fires
+  → Player has NO ADVANCE WARNING — just gets a notification:
+    "The Kwantung Army equivalent has crossed into Korean territory"
+  → Then must choose: endorse or disavow (both bad)
+  → Can REDUCE risk by: strengthening civilian control, keeping military satisfied,
+    maintaining economic prosperity, appointing strong PM
+```
+
+**2. 下克上 (Gekokujō — The Low Overthrow the High)**
+```
+  Junior officers assassinate politicians/seniors they consider:
+  ├ "Too soft on foreigners"
+  ├ "Corrupt" (taking zaibatsu money)
+  ├ "Betraying the Emperor's will"
+  ├ "Selling out to Jianzhou/Song/England"
+  
+  Historical parallels: 
+  ├ 1932 assassination of PM Inukai (5-15 Incident)
+  ├ 1936 attempted coup (2-26 Incident)
+  ├ Various Bakumatsu assassinations
+  
+  V3 MECHANIC:
+  → Event fires when: military anger high + reform happening + specific trigger
+  → "A group of young officers has assassinated [Cabinet Minister/PM/Zaibatsu head]"
+  → Consequences:
+    ├ Political crisis (government paralyzed)
+    ├ Civilian faction weakened (fear of assassination → self-censorship)
+    ├ Military faction emboldened
+    ├ Possible martial law declaration
+  → Player can:
+    ├ Crack down (arrest conspirators, purge military → but weakens army capability)
+    ├ Appease (promote conspirators' allies → but civilian democracy erodes)
+    └ Ignore (pretend it didn't happen → worst option, everyone loses faith)
+```
+
+**3. 軍事政変 (Gunji Seihen — Military Coup)**
+```
+  The ultimate breakdown: military seizes the government entirely.
+  
+  Triggers (all must be high):
+  ├ Military faction power: very strong
+  ├ Civilian government: very weak (scandals, failures, unpopular)
+  ├ Economic crisis: recession or depression
+  ├ External humiliation: lost war, forced treaty, 独走 disavowed
+  
+  Event: "二・二六 equivalent — Military Coup Attempt"
+  
+  If coup SUCCEEDS:
+  ├ Japan becomes military dictatorship
+  ├ Diet suspended or puppetized
+  ├ Aggressive foreign policy (invade Korea? attack Jianzhou? Pacific expansion?)
+  ├ Zaibatsu co-opted (war economy)
+  ├ Civil liberties suppressed
+  ├ → Japan becomes Showa-style militarist state
+  └ → Might lead to overexpansion → catastrophic war → eventual collapse
+  
+  If coup FAILS:
+  ├ Military faction purged (temporarily weakened)
+  ├ Civilian government strengthened (crisis creates reform mandate)
+  ├ Possible: full civilian control of military (finally)
+  ├ But: army morale damaged → defense capability temporarily reduced
+  └ → Window of vulnerability for Jianzhou/Korea to exploit
+  
+  V3: This is the HIGHEST STAKES event for Japan
+  → Player can influence whether it fires (by managing factions)
+  → But if conditions are right, it WILL fire regardless
+  → The outcome depends on player's pre-crisis positioning
+```
+
+**4. 統帥権干犯問題 (Supreme Command Interference Issue)**
+```
+  Recurring political crisis whenever civilian government tries to:
+  ├ Cut military budget
+  ├ Negotiate arms reduction treaties
+  ├ Withdraw from Pacific territories
+  ├ Reduce conscription
+  
+  Military responds: "This violates the Emperor's supreme command authority!
+                     Only the Emperor can decide military matters!
+                     The Diet has NO RIGHT to interfere!"
+  
+  → Government paralysis
+  → Cabinet may resign rather than fight this battle
+  → V3: periodic event that blocks military-related reforms
+  → Only way past it: either get Emperor's support OR push through civilian control reform
+```
+
 ### The Emperor's Role (天皇の役割)
 ```
   Emperor: above politics (officially), but can tilt the balance